Eco driving. It's not exactly a sexy sell. But what if it involved a 450hp 4.4-litre twin turbo V8?
Perhaps that's BMW's reasoning. After all, we've just experienced its latest sat nav-powered and context aware fuel-sipping tech courtesy of the monumental 750i luxury limo and Munich's finest highways and byways.

Incongruous? Probably, but if it's works in the 750i, it'll be even more effective on BMW's more mainstream models.
Efficient Dynamics
BMW's efficiency efforts now dominate pretty much everything the company does. From 1995 to 2008, BMW reduced the average fuel consumption of its range by fully 25 per cent and plans to do the same again by 2020.

But with its rep for building the "ultimate driving machines", BMW has to somehow make efficiency jive with driving fun. Enter Efficient Dynamics, launched in 2007 with a view to doing just that.
At this stage, we could tell you all about what Efficient Dynamics has been. Things like start-stop technology, brake energy regeneration, attention to aerodynamic efficiency and weight.

All that remains true. But what's new is what's really interesting.
Eco Pro
And there's plenty of new stuff to geek over. So let's get going.

First up is Eco Pro. It's just one of a range of driving modes now offered with most BMWs, other examples including various soprt and comfort modes.
If you flip the switch to Eco Pro in our spangly new BMW 750i test car, the first thing you'll notice is the driver's instruments. Suddenly, the rev counter turns into an eco meter.

The fact that the instruments are one big LCD screen (and a very high quality one, at that) is cool enough, though not something you'll get on, say, a basic 1 Series hatch. But is it actually any use?
In simple terms, it means you can tell at a glance the power state of the car. Are you using any energy and how much, are you charging the battery with via brake regen, that sort of thing.

Predictive driving
From there, however, things get a lot fancier. BMW is now using navigation data combined with situational awareness and driving style analysis to provide eco driving advice.
What does that actually mean?

Imagine you're approaching a roundabout but it's over a blind hill. Eco Pro knows the roundabout is coming up and it knows how fast you're going.
So it can calculate the best time to lift off the gas and coast up to the roundabout in the most efficient manner, rather than leaning on the anchors once you brow the hill. And so a little lift-off icon appears in that LCD instrument panel when the time is right.

In our test car, BMW has also implemented a special coasting mode which fully decouples the engine from the transmission and makes for much, much more efficient coasting. In certain situations, it's enough to improve fuel efficiency by a staggering 20 per cent over the official EU cycle numbers.

Nice, but is it legal?
Currently, it's not clear whether such a feature is actually legal in the UK due to an interpretation of the law which could view the decoupling as a loss of control. We'll update when we have final word.

Next is Eco Pro Routes, which doesn't just parse mapping data for the most efficient route, it also squares it with driving style to deliver the most efficient possible route to your destination.
Or so BMW claims, it's pretty hard to check. What we can say for sure is that the decoupled coasting is very apparent and appears to work well. The only slight snag is the lift-off icon, which is difficult to spot.

We think BMW should use its excellent head-up display to provide the driver with much more obvious cues. Constantly glancing down at the instruments is impractical bordering on dangerous.